[R129 SL] R: Soft Top and Roll Bar Indicator Lights On

[Matthias Fouquet-Lapar]

The problem is probably even much less costly. The soft top control unit 
has an error memory ( as have many system components). If for some 
reason the error memory is filled up, the soft-top (and rollbar which 
are a combined in a '96) will fail to operate. Simply read out the error 
codes and clear the memory. I do have the original Mercedes HHT, but 
there are cheap methods to use build a $5 error code reader or you can 
have this done at your Mercedes dealership.

There is a lot of false understanding of electronics out there and it's 
always very easy to sell a replacement unit if you are not familar with 
the car's electronics. The only reason this particular control unit 
fails is if you jump start your car - at least I heard of few cases (and 
even this does not sound logical to me). Of course selling a new 
controller will also fix the problem - but I think in 95% of the cases 
it's unnecessary, but it sure helps the dealersships and spare part 
departements.

If I were you I would follow-up with the detailer, you brought in an 
operational car and they gave you back a car which is not. I think that 
the controller failed in exactly this time-span is probably less likely 
then to win the lottery.

An alternative which is said to work (although I've never seen it work) 
is to pull fuse #8 if I call correctly for a couple of minutes to clear 
the faults, but as far as I remember the faults are stored in 
non-volatile memory

BTW - when I did read out my soft-top error's the last time they were 
about 10 random errors in memory. If you need help to build a test 
reader to need the full table of error codes, please let me know

Kind regards from Paris

- Matthias

> Message: 1

> Date: Wed, 8 Apr 2009 16:23:35 -0500

> From: "Jody Techlin" <starfishsailor at mail.com>

> Subject: [R129 SL] Soft Top and Roll Bar Indicator Lights On - Soft

> 	Top	Control Unit

> To: "Deneal S" <deneals at sbcglobal.net>, Rolfe <seitle at whidbey.com>,

> 	"SL LIST" <r129list at mbcoupes.com>, jimc at windwireless.net,

> 	mercedes at mercedesmailinglist.com, simssj at gmail.com

> Message-ID: <20090408212335.4E82A47808F at ws1-5.us4.outblaze.com>

> Content-Type: text/plain; charset="iso-8859-1"

>

> Hello All,

> The mechanic called this afternoon with the reason why my 1996 SL320's roll bar light and soft top activation button light are lighted.  In my case itr is the soft top control unit which has failed.  This just so happend to coincide with when I had the car detailed but the detailer had nothing to do with the units failure.  The trusted shop I use shopped for the part, if we purchase the replacement part from the MB dealer network it is $2100; if purchasing a remanufactured unit with the same 1 year unlimited mileage warrenty the price is $925 so needless to say we are using the remanufactured unit.  I am surprised the original unit failed with so few miles on the car but age is age I guess. I would like to thank the many people (Daneal, Jim, Rolfe, SJS and others) for their assistance and advice. I was hoping the problem would be much less costly but I guess that's the way the cookie crumbles sometimes. Thanks again one and all.

> Best regards,

> Jody

> 1996 SL320, 29k

> Punta Gorda, FL

>

>

>